Question

Tyloses are found in
(A) Sclereids
(B) Sclerenchyma fibers
(C) Secondary phloem
(D) Secondary xylem

Answer 1

Hint: Tyloses are found in the tissue or cells which help in the transportation of water and nutrients from roots to the shoot and leaves and are formed from the vascular cambium as the result of the secondary growth.

Complete step by step answer:
Tyloses are found in Secondary xylem. Tyloses are an outgrowth structure on parenchyma cells of secondary xylem vessels. The function of these cells is seen when there are unfavorable conditions like drought or plant or vascular bundles that are affected by some infection. During stressed conditions like drought, these tyloses will fall or get detached from secondary xylem and dam up or block the vascular tissue which helps plants to prevent it from the damage.

So, the correct answer is ‘Secondary xylem’.

Additional Information:
- Sclereids- Sclereids is a reduced form of sclerenchyma cells. Scleroid are formed through sclerosis of parenchyma cells. The sclerification increases the disease resistance property of the plant as it increases the thickening of the cell wall.
- Sclerenchyma fibers- Fibres are elongated cells. Both sclereids and fibers are sclerenchyma cells but differ in the shape.
- Secondary phloem- Secondary phloem is formed during secondary growth. Phloem helps in the conduction of the solutes in the plant.

Note: Formation of secondary tissues takes place by the lateral meristem which is of two types i.e vascular cambium and cork cambium. Vascular cambium helps in the production of secondary vascular tissues and cork cambium helps in the formation of the periderm. Cork cambium is also known as phellogen.